A UN official who visited a hospital in the Gaza Strip after local health authorities announced that more than 100 civilians waiting for aid had been killed in an Israeli attack, says some of the injured had gunshot wounds.

The health authorities say Israeli troops attacked a crowd of people waiting for trucks carrying food in northern Gaza on Thursday, killing 115 and injuring 760.

Israeli forces say they fired warning shots but deny shooting people who had gathered to collect supplies.

The incident sparked angry criticism of Israel and calls for a probe by the international community.

An official with the UN Office for the Coordination of Humanitarian Affairs, or OCHA, reported on social media on Friday that medics at Al-Shifa Hospital are treating more than 200 people injured in the attack, some of whom have gunshot wounds.

The humanitarian situation in northern Gaza is worsening as the entry of aid trucks is being hindered by fighting and Israeli inspections at checkpoints.

US President Joe Biden announced on Friday that the United States is planning to airdrop aid supplies into the Gaza Strip following similar measures by Jordan and France.

When asked by reporters if a deal between Israel and Hamas to pause the fighting and release hostages can be reached by the Muslim holy month of Ramadan, Biden said the related parties are working hard, but are not there yet.

The US news website Axios reported on Friday that Israel has told Egypt and Qatar which are acting as mediators that it will not hold another round of talks until Hamas presents a list of the hostages who are alive.